Not applicable.
Not applicable.
This invention relates to fuel modules for delivering fuel to internal combustion engines, and more particularly, to an improved fuel module having an improved jet pump design and an improved return fuel design.
Fuel modules installed in the fuel tank of an automotive engine typically include an electric fuel pump for pumping fuel to an internal combustion engine. Fuel is drawn from the tank into the pump""s inlet through a fuel filter. The fuel pump raises the fuel pressure from a relatively low level to a pressure on the order of from 15-50 psi or greater. The outlet of the fuel pump module is connected to a fuel rail which routes the fuel to the intake manifold of the engine. Any excess fuel is returned back to the module, re-circulated through the fuel pump with new fuel, and returned to the engine for combustion.
Current fuel modules have a number of drawbacks. One is the efficient design and operation of a jet pump such as the pumping mechanism shown in U.S. Pat. No. 4,860,714. Another is the design and operation of a valving mechanism in the return path. Conventional return pump designs include a diaphragm which, if it fails, renders the return valve inoperative. The present invention addresses various problems with current fuel modules to provide an efficient fuel module usable with many internal combustion engines.
In accordance with the invention, generally stated, a fuel module assembly installed in a vehicle""s fuel tank includes a reservoir housing. A fuel pump installed in the housing draws fuel from the reservoir and pumps fuel at high pressure to a fuel injection system for the vehicle""s engine. A manifold also installed in the housing and in fluid communication with the pump outlet routes the fuel through a supply line to the fuel injection system. Fuel not consumed by the engine flows back to the fuel module through a return line so to be discharged into the reservoir for redelivery to the engine. An improvement to the fuel module includes an external jet manifold assembly mounted to the reservoir housing. Fuel from the manifold is directed to the jet manifold assembly and flows through a nozzle portion of the assembly. The jet manifold assembly also includes a venturi into which fuel drawn through the nozzle is discharged. This create a low pressure region and the suction created thereby draws fuel from the tank in which the fuel module is installed into the jet manifold assembly where it is entrained with fuel discharged from the nozzle. The outlet of the jet manifold assembly is in fluid communication with the reservoir to deliver the fuel to the reservoir. The result is that fresh fuel intermixed with recycled fuel is supplied to fuel pump for delivery to the engine.
In addition, the fuel directed back to the fuel module assembly through the return line is discharged into the reservoir through a fuel return valve. The return valve includes a spring loaded plunger mounted in a valve housing. The valve is interposed in the return path to the reservoir. When the engine is shut off, the spring biases the valve closed. When the engine is running, high pressure fuel from the fuel pump is routed through the manifold to act on the plunger and move the plunger against the force of the spring to open the return valve.
Other objects and features will be in part apparent and in part pointed out hereinafter.